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• The characteristics of high-frequency oscillation in MMC-HVDC systems are analyzed and summarized by impedance method. • The influence of the parameters of passive filters on impedance shaping effect is analyzed and summarized. • A passive damping parameter design method which can be implemented based on "black box" model or simplified theoretical model of MMC station is presented in detail. • The proposed method reduces the capacity of the passive damping device while ensuring system stability margin. Recent years, there have been several high-frequency oscillation events in modular multilevel converter (MMC) based DC current projects. Considering the wideband oscillation characteristics of this issue, passive MMC impedance shaping methods are superior solutions for their advantages over the active methods in enhancing the broadband damping level. However, the optimization of parallel passive devices mainly focused on reactive power compensation and the suppression of characteristic harmonics generated by low-level inverters, which is not applicable to MMC systems. To address the optimization design problem of passive damping devices, this paper proposes an optimized design method for passive filters by analyzing the relationship between the passive damping device and the impedance shaping effect of the inverter. The proposed method reduces the capacity of the passive damping device while ensuring system stability margin. Finally, the effectiveness of the proposed passive impedance shaping strategy is verified through time-domain simulations considering changes in AC side operating conditions and power reduction operation of the MMC. [ABSTRACT FROM AUTHOR]

In order to solve the difficulty of characterizing the optical constants of ZnS at high temperatures, the multi-phonon absorption dielectric function model which includes temperature parameters is constructed and modified in this paper. The multi-phonon absorption parameters of ZnS have been inverted based on variable temperature infrared transmittance spectra. The variable temperature infrared transmittance spectra of ZnS have been well fitted. The temperature dependence of the dissociation energy of ZnS materials is demonstrated, and the optical constants of the ZnS material have been obtained at 25 °C, 100 °C, 200 °C, 300 °C, and 400 °C. • The relationship between the value of m max and temperature is established in the multi-phonon absorption model of ZnS. • The ZnS multi-phonon parameters for various temperatures obtained by spectral inversion conform to physical laws. • Highly accurate variable-temperature optical constants of ZnS were obtained based on the multi-phonon absorption model. [ABSTRACT FROM AUTHOR]

The goal of this study was to enhance the utilization of millet straw and reduce N 2 O emissions, used the semi-interpenetrating (Semi-IPN) technology to develop a novel straw-based material (CSC-g-PAA/PPVA) through the composite integration of modified straw and linear polymer (PPVA). The fourier-transform infrared, x-ray diffraction, x-photoelectron spectroscopy and scanning electron microscopy techniques were be measured to provide evidence of the structure and morphology characterization of CSC-g-PAA/PPVA. The results demonstrated that it exhibited excellent water absorbency and enhanced the adsorption capacity of inorganic nitrogen, with the maximum adsorption of NH 4 + and NO 3 - were 94.5 mg/g and 70.3 mg/g, respectively. The properties of CSC-g-PAA/PPVA could significantly reduce N 2 O emissions, which was 42.5–95.7% lower than that of the fertilization groups, demonstrated that the modified material produced in this study had significant potential to reduce greenhouse gas emissions. [Display omitted] • The soil conditioner is derived from corn straw, which can enhance waste straw utilization. • The product is rich in typical functional group, providing active sites for NH 4 +, NO 3 - retention. • The straw-based conditioner has significant potential to reduce N 2 O emissions in soil. • Preparing by waste straw can reduce cost, is beneficial to industrial production. [ABSTRACT FROM AUTHOR]

Humans have innately established close and profound ties with the, and through these relationships shaped many kinds of landscapes. Among these are sacred landscapes, which have drawn the attention of researchers due to their cultural significance. In the field of health geography, large-sized sacred regional landscapes are now the focus of studies for their therapeutic properties. However, few scholars have focused on small sacred landscape systems at the community level (constructed by local communities) or the physical and psycological health benefits that these landscapes offer to the local residents. These small-sized and widespread, but often hidden, sacred landscapes are closely tied to people's daily lives and work. They have evolved and grown over millennia to become critical sociocultural phenomena. This study takes the sacred bao ye landscape of the Dong people of China as the research subject. By adopting the case study approach, field research, semi-structured interviews, and textual analysis, it summarizes the types, geographical distribution, rituals and processes of bao ye as a sacred landscape of the Huanggang village in Guizhou Province, and concludes with an analysis of motivation and health benefits to the bao ye worship. In this paper we argue that bao ye is a sacred landscape system focusing on the healthy development of children, and constitutes a local belief developed in an isolated environment lacking medical resources, which remains in practice. The sacred landscape of bao ye offers a therapeutic environment, providing children with increased opportunities to engage with and build deep connections to nature. Thruogh this process children may develop a bond with nature that inspires them to protect nature on their own accord. We argue that bao ye offers an important case study for understanding the landscape-people-healing interactivity at the community level. • Sacred landscapes have beneficial effects on the physical and mental health of humans. • The community-level sacred landscape of Bao ye is important for the healthy development of local children. • The sacred landscape system of the Dong people helps to better protect this precious traditional cultural landscape. [ABSTRACT FROM AUTHOR]

[Display omitted] • Interaction of flavor substances in sesame-flavor baijiu was studied firstly. • Volatile change was the reason for the interaction affecting the flavor perception. • Structure and phase ratio affected the volatility of esters. • The interaction prediction model is established firstly to realize rapid judgment. The interaction between 1,3-dimethyltrisulfide and aroma-active compounds in sesame-flavor baijiu was evaluated by Feller's additive model and Odor Activity Value Approach, and the reason for the interaction can promote the release of fruity and caramel aromas of ethyl caproate, ethyl was explored by the Partition Coefficient Approach. The interaction results indicated that 1,3-dimethyltrisulfide caprate and furan-2-ylmethanol. Others showed masking effect. The Partition Coefficient showed that the effect of 1,3-dimethyltrisulfide on the volatility of esters was one of the reasons for the interaction affecting the flavor perception, and the volatility of ethyl esters with longer carbon chains at high phase ratio (PRs) is more likely to be promoted. Besides, the prediction model was initially proposed: y = 2.0112 ln(x) + 0.1461, which indicated that esters with the olfactory threshold lower than 33.80 μg/L are more likely to have positive effects with 1,3-dimethyltrisulfide, the negative effect is more likely to occur conversely. [ABSTRACT FROM AUTHOR]

• Melanoidins were mostly produced during distillation. • Melanoidins were primarily composed of carbohydrates. • Melanoidins formed during fermentation and distillation had structural differences. • Carbohydrates, proteins and phenols are involved in melanoidin formation diversely. Chinese liquor (baijiu) is a typical fermented food. In which production, melanoidins are formed in fermenting grains during low-temperature fermentation with long-term, and in distilled grains with high-temperature distillation for short-term. Here, the formation and structural characterization of melanoidins in these two distinct stages were first investigated through chemical composition analysis and spectroscopic identification. Our research showed that proteins and phenols continuously participate in melanoidin formation during fermentation and distillation processes. Distillation could produce melanoidins with larger amounts, darker colors, higher molecular weights, and more stable states than fermentation. The chemical composition including 10 carbohydrates, 17 amino acids, 5 free phenolic acids, and 7 bound phenolic acids was successfully identified in melanoidins. Ion chromatography was proposed to be an efficient method to investigate carbohydrates in melanoidins. Moreover, the potential impact of microorganisms on melanoidins was first revealed to be the possible utilization of glucose in melanoidins. [ABSTRACT FROM AUTHOR]

The goal of this study was to enhance the utilization of millet straw and endow it with the fertilizer function through modifying the carboxymethylcellulose (CMC-NH 4), based on wheat straw, by acidification and ammonification to improve water and fertilizer efficiency. Amine group was introduced through the electrophilic substitution to supply nutrients to crops. The order of influential factors on the water absorption property was determined by an orthogonal experiment and showed that the highest water absorbency of 224.7 g/g, which was achieved for the conditions of 3:1 carboxymethylcellulose to nitric acid solution (mass percentage concentration of 50%), 3:1 carboxymethylcellulose to ammonia solution with the mass percentage concentration is 30%. The CMC-NH 4 was characterized by scanning electron microscopy, fourier-transform infrared, x-ray diffraction, and X-ray photoelectron spectroscopy techniques, and the results indicated that application of CMC-NH 4 promoted the growth indexes of wheat, improved wheat yields. Therefore, the waste straw was modified into the soil conditioner with specific function by the group targeted modification strategy. In addition, the fertilizer efficiency and water-retention behavior of CMC-NH 4 encouraged its use as a safe water- and fertilizer-retaining agent in agricultural applications. [Display omitted] • The product prepared by straw can reduces cost, is easy for agricultural extension. • The CMC-NH 4 is rich in ammonium, could provide fertilizer for crop growth. • The product shows excellent water retention and could prevent water percolation. [ABSTRACT FROM AUTHOR]

Based on the standardized Euclidean distance method, an evaluation theory for sustainable agricultural development was constructed, which includes a sustainable agricultural development model, an evaluation function model, a sustainable agricultural development exponent (SADE), a rank of the sustainable agricultural development, an index frame of the sustainable agricultural development, a goal system, and a zero system. Data from Zhenyuan County of Gansu province (ZYC) between 2000 and 2012 was used as a case study of the theory. The SADE of ZYC was [0.34, 0.90], and the agriculture system exhibited low sustainability from 2000 to 2003, mid sustainability from 2004 to 2007, and high sustainability from 2008 to 2012. The results explained the actual ZYC situation, and showed that the Euclidean distance method of sustainable agricultural development is feasible. The innovativeness and merits of the method include: (1) reliable methodology, (2) construction using goal and zero systems, which serve as reference systems of sustainable agricultural development and allow control of the evaluation, and (3) index weights embedded in the evaluation function, which prevents errors or mistakes in the expert scoring method and prevents the reassignment of index weights due to adding or subtracting indicators. The main reasons that the SADE increased in ZYC include suitable chemical fertilization and pesticide application, enhancement of conservation farming areas, soil testing and fertilizer-formulated areas, and drinking water security in rural and non-disaster crop areas. The main problems with increasing the SADE in ZYC include straw application and low farmer income, both of which should be increased. [ABSTRACT FROM AUTHOR]

• High-frequency resonance is suppressed by broadband MMC impedance reshaping. • Phase compensation is adopted to eliminate the negative damping of MMC. • The proposed method is effective under various operating scenarios of ac grid. • A controller parameter design method is presented in detail. Negative damping in modular multilevel converter (MMC) impedance may lead to high-frequency resonance (HFR) in MMC-high-voltage direct current systems. The existing solution is based on amplitude attenuation by digital filters. However, filters have weak amplitude attenuation and obvious phase shifts in the attenuation band, resulting in the transfer of negative damping. The system still has a risk of HFR when grid condition is changed. This study proposed a broadband active damping method based on phase compensation to address this limitation. The embedding position and scheme of the phase compensation controller are optimally designed through impedance-based analysis. By tuning parameters correctly, the negative damping of MMC is eliminated over a wide frequency range (500–2000 Hz). Thus, the proposed method performs better in HFR suppressing under varying grid conditions. In addition, considering the harmonic amplification problem caused by the differential link, an inertia link and a proportional link are further employed to increase high frequency impedance magnitude. Time-domain simulations in MATLAB/SIMULINK verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In this study, a novel “net-like” nanostructured cell-substrate interface to enhance the human osteoblast cell's functions in orthopedic applications was proposed. This novel “net-like” nanostructured surface was fabricated on 316L stainless steel by using ultrasonic shot peening. The in vitro study indicated that this “net-like” nanostructured cell-substrate interface could significantly enhance the attachment, spreading and proliferation rate of the human osteoblast cells (Saos-2) compared with the as-received surface with coarse grains. The enhancement of cell functions could be attributed to the high density grain boundaries in the “net-like” nanostructured surface, which could promote protein adsorption when material comes in contact with biological environments. [ABSTRACT FROM AUTHOR]

Abstract The correlations between the average linear thermal expansion coefficient < α > and glass transition temperature T g and between GV m (G is shear modulus and V m is molar volume) and T g for a variety of metallic glasses (MGs) were investigated. A Lindemann-like equation, < α > × T g = 0.75 × 10−2, is observed, indicating that the glass transition of MGs follows Lindemann-like rule. The relationship provides a new perspective to understand the mechanism of glass transition and a simple method to predict T g for a given MG. Additionally, T g is found to vary linearly with GV m , implying that an inherent relevance between glass transition and plastic deformation of MGs. Highlights • A Lindemann-like equation, < α > × T g = 0.75 × 10−2, is observed. • T g is found to vary linearly with GV m. • These relationships provide a perspective to understand the glass transition and plastic deformation of MGs. [ABSTRACT FROM AUTHOR]

In order to enhance utilization of millet straw and reduce fertilizer loss, a novel multifunctional fertilizer (MS-g-PAA/PDMUA) was developed using straw cellulose and linear polymer (PDMUA) by semi-interpenetrating technology. The structure and morphology characterization of MS-g-PAA/PDMUA were measured by fourier-transform infrared, x-ray diffraction, x-photoelectron spectroscopy and scanning electron microscopy techniques, to provide evidence of semi-IPNs networks and component interactions, and the results show that the product exhibited excellent water absorbency (562.3 g/g) and enhanced the soil infiltration. Cumulative release of N, P was 49.2% and 55.1%, respectively, after 40 days, coming up to the Committee of European Normalization (CEN) standard. The agricultural application of MS-g-PAA/PDMUA showed that it could promote growth indexes of wheat, which could improve wheat yields. Therefore, desirable water retention, slow-release properties, and wheat growth effects highlight the product's potential for agriculture application. [Display omitted] ● MS-g-PAA/PDMUA is derived from millet straw, can enhance waste straw utilization. ● The MS-g-PAA/PDMUA is rich in nitrogen and phosphorus, which promote wheat growth. ● The product has excellent water retention and slow fertilizer-release properties. ● Preparing by waste straw can reduce cost, is beneficial to industrial production. [ABSTRACT FROM AUTHOR]

• A steady cone-jet occurs in a greater range of liquid flow rates for a hemispherical capillary. • Varicose and whipping regimes are easily obtained with a hemispherical nozzle. • The transition from varicose and whipping usually depends on interfacial forces on the jet. • A general parameter to determine varicose, transition, and whipping regimes is presented. A cone-jet regime in electrohydrodynamic atomization (EHDA) is widely applied into printing, electro-spinning, spray-coating, and biological mass spectrometry. Regulating different instabilities of jet is crucial for optimizing its operating parameters. In present work, an atypical, hemispherical capillary with inner diameter of 0.40 mm and cap size of 6.20 mm was employed as atomization nozzle, through which a steady cone-jet regime was confirmed versus suitable feeding liquid flow rate and electric potential. A permanent and highly charged jet emits from a Taylor cone apex and further disintegrates into fine highly charged drops in the form of varicose or whipping instabilities. The results indicate that a steady cone-jet is observed in the specific ranges of the feeding liquid flow rate, electric potential and conductivity. The typical breakup instabilities including varicose and whipping are clearly observed with an increase in liquid flow rate for a fixed electric potential for most of liquids, and the transition from varicose to whipping instability easily occurs. For a steady cone-jet, the jet breakup instabilities usually depends on the competition between interfacial forces on the electrified jet. The transition process involving a low-viscosity jet with a large flow rate is observed, and the general parameter G = Γ 2 δ μ 0.52 is calculated to account for surface charge, surface tension, and viscosity effects, where Γ is the electric force to surface tension ratio and δ μ is the inertia to viscous force ratio. Finally, the varicose, transition regime, and whipping are classified with first and second critical threshold values G = 40 and G = 102, respectively. Meanwhile, as the electrified jet transforms from varicose to whipping instabilities, the jet breakup length shows a trend of increasing first and then decreasing. [ABSTRACT FROM AUTHOR]

Abstract: This paper focuses on the gas sensing properties of the mixed-potential-type NO2 sensor based on yttria stabilized zirconia (YSZ) and NiO electrode. The sensing performance of the sensor was improved by modifying the three-phase boundary (TPB). Hydrofluoric acid with different concentrations (10%, 20% and 40%) was used to corrode YSZ substrate to obtain large superficial area of TPB. The scanning electron microscope and atomic force microscopic images showed that the 40% HF could form the largest superficial area at the same corroding time (3h). The sensitivity of the sensor using the YSZ plate corroded with 40% hydrofluoric acid to 20–500ppm NO2 was 76mV/decade at 850°C, which was the largest among the examined HF concentrations. It was also seen that the sensor showed a good selectivity and speedy response kinetics to NO2. On the basis of the measurements of anodic and cathodic polarization curves, as well as the complex impedance of the device, the sensing mechanism was confirmed to involve a mixed potential at the oxide sensing electrode. [Copyright &y& Elsevier]

• The necking time is independent of electric field in a reasonable range of flow rate. • The transition from dripping to jetting is enhanced by electric field for relatively small tube. • A model for the transition from periodic dripping to jetting is established in an electric field. • A critical criterion for the transition is presented and in reasonable agreement with experiments. A liquid is issued from the outlet of the capillary tube vertically, and drop formation may be in the form of periodic dripping, dripping faucet and jetting, which usually depends on flow rate or Weber number. We consider the critical Weber number (W e C = ρV 0 2 D / σ) at which the transition from periodic dripping to jetting occurs in the presence of an electric field, where high-resolution images are recorded. The necking time is mainly related to nozzle diameter and surface tension, and independent of electric potential and flow rate (in a reasonable range).The first threshold limit decreases with an increase in electric potential, where the dripping faucet is clearly affected and the point of drop detachment gradually increases. When the drop formation is in the form of dripping faucet, the transition from dripping faucet to jetting regime is enhanced by electric potential, where a sudden transition could be observed in an extremely limited range of liquid flow rate. The critical criterion (Weber number) is presented to determine the transition from dripping to jetting in the presence of an electric field. The critical Weber number is in a reasonable agreement with the experiment, although the predicted results are quantitatively divergent with experimental data. [ABSTRACT FROM AUTHOR]

To enhance waste straw utilization and improve fertilizer efficiency, a novel semi-interpenetrating polymer network fertilizer (CMCK-g-PAA/PDMUP) was prepared from straw cellulose and linear polymer by solution polymerization. Polydihydroxymethyl-urea potassium phosphate (PDMUP) was included to supply nitrogen, phosphorus, and potassium nutrients. Characterization of CMCK-g-PAA/PDMUP with FTIR, XPS, XRD, and SEM techniques provided evidence for semi-interpenetrating polymer networks (semi-IPNs) and component interactions. The prepared product exhibited excellent water absorbency (681.3 g/g) and enhanced the soil's water-retention capacity. Cumulative release of N, P, and K was 56.1%, 64.3%, and 74.1%, respectively, after 40 days–meeting a Committee of European Normalization (CEN) standard. Agricultural application of CMCK-g-PAA/PDMUP promoted wheat growth. Desirable water retention, slow-release properties, and wheat growth effects highlight the product's potential for improving agriculture. Unlabelled Image • Application of the polymer (CMCK-g-PAA/PDMUP) could achieve utilization of waste straw. • The CMCK-g-PAA/PDMUP is derived from waste straw and rich in fertilizers (N, P and K). • The product had excellent water retention and slow-release properties. • The product prepared by waste straw can reduces production cost and promote plant growth. [ABSTRACT FROM AUTHOR]

Hydrocarbons with four carbons in their molecular structure (C4s) represent an important chemical family in the modern petrochemical industry. Converting less valuable C4s into more valuable C4s with effective separation has been of significant industrial interest. The large variety of C4s leads to a complex reaction pathway network. Prior work carried out on C4 modelling and optimisation has been largely industry-focussed with limited studies found in academic publications. This work aims to bridge the research gap by developing a systematic methodology that can identify the optimal process pathways for maximum economic return. A superstructure network is developed, showing comprehensive pathways for C4 processing. Mathematical programming is applied to model the superstructure with individual processing units, in which simplified process models used in the network model can be supported by detailed process models. Optimisation is implemented in GAMS, the results of which help gain important physical insights into the best options for C4 processing. [ABSTRACT FROM AUTHOR]

A two-stage process has been developed for the pyrolysis of high-density polyethylene to obtain light olefins, where probable mechanisms for each stage pyrolysis were proposed in our previous study. This work aims to establish molecular-level kinetic models for the first-stage pyrolysis at a lower temperature and for the second-stage pyrolysis at a higher temperature, respectively, to predict the overall reaction performances in accordance to the role of detailed mechanisms. A structure-oriented lumping (SOL) method based molecular-level kinetic model can effectively describe the first-stage pyrolysis, while a detailed molecular-level kinetic model is developed for the second-stage pyrolysis to track the evolutions of all alkanes, olefins, and diolefins, with special focus on the formation of light olefins. The established separate models can achieve the automatic generation of complex reaction networks and present good agreement with experimental data obtained from the first- and second-stage. In addition, the first-stage model indicates that the random scission plays an important role in the pyrolysis process at lower temperatures, while the chain-end scission mechanism dominates the second-stage reaction to produce light olefins at higher temperatures. As a whole, the molecular-level modelling scheme behaves excellently at a wide range of temperature, which provides guidance for upgrading the pyrolysis process. • A molecular level kinetic model is established for the two-stage HDPE pyrolysis. • The reaction network is generated automatically and visualized. • This model achieves excellent agreement with experimental data. • The competition of two scissions and important role of temperature are quantified. [ABSTRACT FROM AUTHOR]

• The onset and termination electric potential to form the steady cone-jet electrospray increase as conductivity increasing. • The lower and upper limitation of liquid flowrate to form the steady cone-jet electrospray decrease as conductivity increases. • The varicose instability can transform into whipping instability as the electrical conductivity increasing. • The jet breakup instability transition mechanism is interpreted by theoretical analysis. • The whipping to similar micro-dripping instability can be observed for EG with higher conductivity. In present work, the effect of the electrical conductivity on the steady cone-jet electrospray are experimentally investigated, where the operating diagram and the jet breakup instability are extensively examined. A hemispherical tube is employed as spraying nozzle severed as high electric potential electrode in a needle-plated electrode configuration compared to the common and sheathed tubes. The cone-jet electrospray is visualized by a high-resolution camera and extensively analyzed offline. The aqueous solution in ethanol, Diethyleneglycol (DEG) and Ethylene glycol (EG) are atomized with varied electrical conductivity under different high electric potentials and flowrates. Experimental results indicate that the cone-jet electrospray can operate in the certain ranges of operating parameter for all types of capillaries. The operating diagram for the hemispherical tube is significantly broader than other tubes because of various electric field strength distribution. The onset electric potential to determine a steady cone-jet electrospray gradually increases and the termination value also increases as the electrical conductivity increases. The lower and upper flowrate to form a steady cone-jet electrospray also increase as the electrical conductivity increases. The jet breakup instability can transit from varicose to whipping due to low the reference flow rate as electrical conductivity increases, which is agreement with theoretical analysis. In particular, for EG, the transition from whipping to similar micro-dripping is observed as the electrical conductivity increases, while the transition also occurs as flowrate increases for EG with higher electrical conductivity. The increase in the electrical conductivity and flowrate elongates the cone due to EHD body force, which causes the electric field varying, further resulting in the difference in jet breakup instability. Moreover, the electrical conductivity also plays an important role in jet breakup length. The instability variation of jet with conductivity (DEG), q V =1000 nL/s, ϕ =8.00 kV (Hemispherical nozzle with D o =0.70mm); The variation with liquid flow rate of EG with higher conductivity (K =8.5 × 10−4 s/m, ϕ =10.20 kV, (Hemispherical nozzle with D o =0.70mm) [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • FeNi nanoalloys were encapsulated in graphitic carbon nanofibers derived from Prussian blue analogue (PBA). • Limited oxidation and aggregation of FeNi nanoalloys in CNF were obtained by changing PBAs loading. • Synergistic effect between non-noble plasmonic nanoalloys and graphitic carbon nanofibers was constructed by electrospinning. • Optimized photothermal conversion efficiency was reached by the constructed composited fiber membrane. • A extremely low usage dosage of photothermal materials can enable the construction of 2D evaporation membrane. Sustainable and energy-efficient water purification by harnessing solar energy is critical to tackling the challenges of water scarcity and the on-going water pollution crisis. Nevertheless, the biggest challenge to the practical deployment of solar-driven water purification, however, continues to be the poor solar evaporation efficiency of materials. Herein, FeNi nanoalloys encapsulated in graphitic carbon nanofibers (FeNi 3 /CNF) using Prussian blue analogue (PBAs) derivatives were fabricated using electrospinning and carbonization. The PBAs metal precursors play a critical role in encapsulating and safeguarding the FeNi alloy nanostructures from oxidation and agglomeration challenges. Furthermore, the synergistic effects between the non-noble hybrid plasmonic nanoalloys and graphitic CNFs can be constructed and optimized from the mass loading of PBAs precursor. Benefiting from the broad solar absorption band, high specific surface area, abundant micro-mesopores, and well-organized interlayer channel, the resultant 2D FeNi 3 /CNF solar evaporator demonstrates an efficient water evaporation rate of 1.51 kg m-2h−1 with an outstanding solar evaporation efficiency of 93.3 % under one sun irradiation, among the best values reported thus far. Impressively, the resultant 2D FeNi 3 /CNF solar evaporator can be constructed using only 0.02 kg m−2 loading of photothermal materials without compromising evaporation performance, which highlights its cost-efficiency in the practical application. Furthermore, the desalinated water meets the drinking standards of the World Health Organization (WHO) with an efficient 99 % separation of multiple organic industrial dye pollutants. Hence, this work demonstrates an efficient cost-effective approach to novel non-noble plasmonic alloy-based metal–carbon composites for enhanced solar-driven interfacial evaporation and wastewater purification. [ABSTRACT FROM AUTHOR]

Waste plastics have emerged as a global environmental issue. Polyethylene, accounting for about 25% of global plastic production, has been acknowledged as the major cause of "white pollution". In this paper, a generalized molecular-level kinetic model was proposed to understand the pyrolysis of polyethylene applying structure-oriented lumping, Poisson distribution, and genetic algorithm. The number of ordinary differential equations derived from the reaction kinetics were dramatically reduced by this simplified network with 14-rule design. The generalizability was confirmed by case studies without any change in the rule design. Under most conditions, the mean relative error between experimental and model data could be controlled within 5%, while abnormal deviations indicate the obstacle of heat transfer. The simulation curve could provide guidance for the experiments by locating the peak value of products. From 400–470 °C in Case 2, the increase in the reaction proportion of producing light oil explains the experimental results from the perspective of molecular-level reaction network. The comparison between PE and PS pyrolysis elaborates different pyrolysis mechanisms based on the different molecular structures. • Established a generalized molecular-level model for polyethylene pyrolysis. • Offered an efficient tool avoiding repeated work in pyrolysis simulation. • Confirmed the generalizability by case studies without changing the rule design. • Provided guidance for the experiments by locating the peak value of products. [ABSTRACT FROM AUTHOR]

The accumulation of waste plastics has been one of the most urgent and difficult environmental challenges. In this work, the pyrolysis of polyethylene (PE) has been studied by thermogravimetric analysis (TGA), pyrolysis/gas chromatography/mass spectrometry (PyGC-MS), and a two-stage tube reactor. The pyrolysis behavior of high-density polyethylene (HDPE) and low-density polyethylene (LDPE) is compared, and there are almost no differences in the thermogravimetric curves obtained by TGA and the yield of gaseous products obtained in a two-stage process. The evolution of light olefins (C 2 –C 4) during the pyrolysis of PE is investigated in a two-stage process with a constant condition in the first stage (500 °C) and various conditions in the second stage (700–1000 °C, 0.2–0.4 s). The temperature in the second stage has a more significant effect on the yield and selectivity of light olefins than the residence time, and the ethylene, propylene, and butene yields do not increase monotonously as the temperature rises. The highest yield of light olefins of 76.1 wt% is obtained at 800 °C with a selectivity of 91.7%. The maximum yields of ethylene, propylene, and butene are 45.1 wt%, 17.3 wt%, and 24.3 wt%, respectively. The scission mechanisms are proposed to provide insight into the process during which PE molecules transform into light olefins. • There are almost no differences between the pyrolysis characteristics of high-density and low-density polyethylene. • The evolution of light olefins during the polyethylene pyrolysis is investigated by PyGC-MS and a two-stage tube reactor. • A high yield of light olefins of 76.1 wt% with a high selectivity of 91.7% is obtained at 800 °C. • Probable mechanisms for two-stage pyrolysis of PE are proposed to reveal the interplay of reactions. [ABSTRACT FROM AUTHOR]

High-energy lithium-ion batteries (LIBs) have been actively pursued for practical applications in advanced electric vehicles and large-scale energy storage systems. The silicon (Si) material has been considered as a promising anode candidate due to its impressive lithium storage capacity, but is facing the challenge to ameliorate its cycling and rate performance. We here report a structure integration strategy to overcome major issues of poor capacity retention and slow kinetics during the lithium storage of Si anode, through in situ embedding Si nanoparticles into V 2 C MXene nanosheets. The MXene-supported Si@V 2 C nanocomposite anode reveals significantly enhanced cycling stability and improved lithium storage kinetics compared to that of the pristine Si anode. A high capacity exceeding to 430 mAh g−1 can be retained for 150 cycles at 200 mA g−1 current density. In addition, the conductive MXene supporter has been demonstrated to facilitate lithiation/delithiation processes for the Si by enhancing the charge transfer kinetics, as it is demonstrated by in situ electrochemical impedance spectroscopic (EIS) and Galvanostatic Intermittent Titration Technique (GITT) measurements. Findings from this work may inspire feasible structural designs for the practical deployment of MXene composited Si anode materials for next-generation lithium-ion batteries. [Display omitted] • Si@V 2 C composite anode was explored using V 2 C MXene as supporting substrate with enhanced Si stability performance. • A high capacity of 430 mAh g−1 can be retained for 150 cycles at 200 mA g−1 current density. • The V 2 C MXene can provide improved electronic conductivity and structural support of the Si anode during cycling. [ABSTRACT FROM AUTHOR]

Our study developed the one-step catalytic cracking conceptual design using a two-stage riser reactor (OSCO). Molecular-level process models and multi-objective optimization strategies are also carried out. Results show that the OSCO process exhibits superior techno-economic, society, people's livelihood, and environmental performance. [Display omitted] • A novel process is proposed to crack naphtha, kerosene, diesel and heavy oil in the two-stage riser reactor efficiently. • A novel integration model of mixed fraction structure and molecular level is proposed. • The multi-objective optimization strategies using systematic solution algorithm are performed. • The novel process shows superior techno-economic, society, people's livelihood, and environmental performance. With the demand for vehicle fuels (i.e., gasoline and diesel) is expected to decline soon, crude oil to chemical technology exhibits great potential to drive the next industry transition. This megatrend has led to studies on maximizing the production of low-carbon petrochemicals at the cost of fuels, which requires aggressive ways of converting oil into chemicals in a clean and efficient pattern. Herein, we proposed a novel process, termed OSCO, to crack naphtha, kerosene, diesel and heavy oil in a two-stage riser reactor efficiently, which can perform several refining procedures in the two-stage riser reactor vessel. A novel integration model of mixed fraction structure and molecular level is proposed. The multi-objective optimization strategies are also carried out to solve the optimization problem. As a result, the OSCO process can stably convert untreated heavy Daqing crude oil into light olefins with total yields of ethylene and propylene over 33 wt%, which also exhibits superior techno-economic, society, people's livelihood, and environmental performance. These insights may have a positive pushing role in engineering design, process intensification, and the optimization of direct catalytic cracking of crude oil. [ABSTRACT FROM AUTHOR]

[Display omitted] • A rational coating-integrated-into-synthesis design was used to prepare surface Ti-enriched NMC811 material. • The Ti substitute has a unique tri-valence (Ti3+) in a gradient surface distribution. • The surface Ti-enriched NMC811has high cationic ordering both in the bulk and surface. • Theoretical simulations certify enhanced stability of lattice oxygen for the NMC811#Ti material. • The NMC811#Ti cathode shows improved cycling performance and thermal/ storage stabilities. High-Ni cathodes are being intensely pursued worldwide for electric vehicles and other energy-dense applications due to their high capacity and low cost. However, structural instabilities during electrochemical cycling and when subjected to thermal treatment have been the major issues hindering their practical deployment. We here report a rational design of coating-integrated-into-synthesis protocol for fabricating surface Ti-enriched LiNi 0.8 Mn 0.1 Co 0.1 O 2 (NMC811#Ti) material. The coating to intermediates is crucial to obtain high structural ordering, both in the bulk and surface of high-Ni cathodes, and the Ti substitute has a unique tri-valence (Ti3+) in a gradient surface distribution. The simulations of projected density of states in the atomistic understanding further certify significantly enhanced stability of lattice oxygen for the NMC811 through such a Ti3+-based structure reinforcement. Consequently, the NMC811#Ti cathode delivers a high capacity up to 200 mAh g−1 at 0.1 C, along with superior stabilities during air-storage and thermal treatment (up to 297 °C at the fully charged state under differential scanning calorimetric measurements). The corresponding NMC811#Ti||graphite full cell exhibits a desired 83.6 % capacity retention after 1000 cycles at 0.5 C in a voltage range of 2.8–4.3 V. This work demonstrates a delicate surface reinforcement to stabilize high-Ni cathodes for long-life and safe lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Incompatible cross-platform detection technologies adopted for different medical scenarios has caused several problems in the clinical detection of disease biomarkers. Here, we developed a unified platform with hierarchical performance for biomarker detection. A hexagonal star-nanostructured DNAzyme was constructed. It shows excellent catalytic activity towards the deposition of polydopamine, which is capable of presenting colorimetric signals directly and is also scalable to present fluorescent and electrochemical signals by conjugating with quantum dots. This scalable detection system is validated for the detection of both nucleic acid biomarkers (miRNAs) and protein biomarkers (carcinoembryonic antigen and platelet-derived growth factor). Results show that the detection system can adapt to the current colorimetric, fluorescent and electrochemical equipment, possess the advantage of high efficiency and low-cost, and present hierarchical performance in terms of operability and sensitivity, making it possible to verify the results in a unified system and to switch the detection methods according to different scenarios. [Display omitted] • The unified platform showed excellent advantages in efficiency and cost of biomarker detection. • A nanostructured DNAzyme was constructed to realize efficient deposition of dopamine. • The scalable platform is validated for the detection of both nucleic acid and protein biomarkers. [ABSTRACT FROM AUTHOR]

Thrombospondin (TSP) 1 is a trimeric multidomain protein that contains motifs that recognize distinct host cell receptors coupled to multiple signaling pathways. Selected TSP1-induced cellular responses are tyrosine kinasedependent, and TSP! contains epidermal growth factor (EGF)-like repeats. Specific receptor interactions or functions for the EGF-like repeats have not been identified. We asked whether one or more biological responses to TSP! might be explained through EGF receptor (EGFR) activation. In A431 cells, TSP! increased autophosphorylation of Tyr1068 of EGFR in a doseand time-dependent manner. The ability of TSP1 to activate EGFR was replicated by the tandem EGF-like repeats as a recombinant protein. The three EGFlike repeats alone produced a high level of Tyr-1068 phosphorylation. EGF-like repeats from TSP2 and TSP4 also activated EGFR. Tyr-1068 phosphorylation was less when individual EGF-like repeats were tested or flanking sequences were added to the three EGF-like repeats. TSP1 and its EGF-like repeats also increased phosphorylation of EGFR Tyr-845, Tyr-992, Tyr-1045, Tyr-1086, and Tyr-1173, activated phospholipase Cγ, and increased cell migration. No evidence was found for binding of the EGF-like repeats to EGFR. Instead, EGFR activation in response to TSP1 or its EGF-like repeats required matrix metalloprotease activity, including activity of matrix metalloprotease 9. Access to the ligand-binding portion of the EGFR ectodomain was also required. These findings suggest release of an endogenous EGFR ligand in response to ligation of a second unknown receptor by the TSPs. [ABSTRACT FROM AUTHOR]

Gaseous pollutants transport inside liquid micro-cylinders with internal circulations in an equilateral triangular configuration is simulated to study the effects of varied gap-ratio (1 ≤ G / R ≤ 4), Reynolds (Re) number (30 ≤ Re ≤ 160) and incident angle (α = 0° , 30° and 60°) on the absorption in a uniform gaseous stream. The shear stress fluctuates with spatial position on the interface due to unsteady flow separation and attachment. Furthermore, the 'primary' and 'secondary' vortexes inside liquid micro-cylinders are induced, respectively, where soluble gaseous pollutants are quickly entrained and partially blocked into liquid micro-cylinders by 'inflow' and 'outflow' type circulations pair at the stern regions, respectively. For incident angles α = 0 ° and α = 60 ° , the symmetric flow forms because of the symmetric configuration of liquid micro-cylinders, while for incident angle α = 30 ° , the asymmetric flow appears due to asymmetric arrangement. The 'primary' (large clockwise) and 'secondary' (small counterclockwise) vortexes usually depending on Re number and G / R facilitate gaseous pollutants intrusion into liquid micro-cylinders at separation point. The sensitivity of gap-ratio is presented based on the transient accumulation (m so 2 ′), which characterizes the exact influence of G / R. The larger gap-ratio facilitates faster saturation of sulfur dioxide inside liquid micro-cylinders because of fully developed internal vortexes. As R e number increasing, the gaseous pollutants transport could be significantly enhanced because internal vortexes become gradually stronger. In addition, the incident angle has no significant effect on pollutants transport inside liquid micro-cylinders because of slightly direct interaction between separated shear layers and wakes. [ABSTRACT FROM AUTHOR]

• The stable cone-jet occurs in a certain range of electric potential and flow rate. • The electrified meniscus forms appears successively convex, linear sides and concave with an increase in electric potential. • The jet breakup transits from varicose to kink instability with an increase in flow rate. The cone-jet is one of the most interesting means in electrohydrodynamic atomization (EHDA) for wide applications because of highly charged and monodisperse drops. The pulsating and stable cone-jet modes in EHDA of diethyleneglycol (DEG) are observed by means of high-speed photography technology, as well as the breakup modes transition of electrified jet from varicose to kink instability. The conductive liquid is driven to form a liquid cone at the outlet of the capillary tube, and form a permanent jet from the apex of the cone by the tangential electric stress. With an increase in electric potential, the cone angle and jet length increase. The electrified meniscus and the cone may appear convex, linear sides and concave in cone jet regime, which depends on the static equilibrium of forces exists at each point of electrified liquid surface. The jet breakup modes with multi-jet, varicose and kink instabilities are successively recorded as liquid flow rates increasing. The jet breakup transition depends on flow rate. The drops size rises proportionally with an increase in liquid flow rate or a decrease in electric potential in stable cone-jet mode. The dimensionless diameter d / d 0 as a function of the dimensionless flow rate q V / q m is in good agreement with the universal scaling laws. [ABSTRACT FROM AUTHOR]

• Pyroptosis is a pro-inflammantory type of regulated cell death in CVD and gasdermin family is the effector. • Caspase-3/GSDME and caspase-8/GSDMD also can induce pyroptosis. • Targeting to pyroptosis-related pathway provides a promising research direction for the treatment and diagnosis of CVD. Pyroptosis is a pro-inflammatory type of regulated cell death (RCD) characterized by gasdermin D (GSDMD)-mediated membrane pore formation, cell swelling and rapid lysis, followed by the massive release of pro-inflammatory mediators such as interleukin-1β and interleukin-18. There are two main pathways of pyroptosis: the caspase-1-mediated canonical pathway and the caspase-4/5/11-mediated noncanonical pathway. However, the caspase-3-gasdermin E (GSDME) pathway and caspase-8-GSDMD pathway also induce pyroptosis. Pyroptosis can not only cause local inflammation but also lead to amplification of the inflammatory response. Recent studies have suggested that pyroptosis is closely related with cardiovascular disease (CVD); for example, in atherosclerosis, myocardial infarction, ischemia-reperfusion injury, heart failure, coronary calcification and aortic aneurysm, study results have promoted the development of inhibitors targeting the components related to pyroptosis, and some agents have been clinically proven to have cardiovascular benefits. In this review, we summarize emerging evidence to discuss the progressive understanding of pyroptosis and the pathways, effect and effectors of pyroptosis, as well as the role of pyroptosis in CVD. Additionally, we summarize pyroptosis-related pathway inhibitors and classic cardiovascular drugs targeting pyroptosis. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the alterations of brain volumetry and associated structural covariance at lobar level in cerebral small-vessel disease (CSVD) with and without cognitive impairment.Method: Twenty-seven CSVD patients with mild cognitive impairment (CSVD-MCI), 37 CSVD patients with normal cognition (CSVD-NC), and 35 controls, underwent T1-weighted imaging of magnetic resonance. Volume of gray matter (GM) and white matter (WM) and a lobar atrophy index that measures the ratio of cerebrospinal fluid to brain parenchyma were quantified for each lobe. One-way ANOVA with multiple comparison corrections was performed to compare these volumetric measures. Volumetric structural covariance analyses were performed with lobar atrophy indexes to investigate the alterations of anatomical covariance within each pair of lobar regions in CSVD-NC and CSVD-MCI subjects compared with controls.Results: CSVD-NC subjects presented no significant volumetric differences with controls in any of the lobar regions. Compared with controls, CSVD-MCI patients presented significantly smaller volume of GM in bilateral frontal and parietal lobes, significantly smaller volume of WM in right cingulate lobe, and significantly larger lobar atrophy indexes of bilateral temporal, insular lobes and left cingulate lobe (P < 0.05). Both CSVD-NC group and CSVD-MCI group showed significant differences of structural covariance as measured by lobar atrophy index compared with controls. In particular, CSVD-MCI group showed even more extensive alterations of structural covariance, especially in bilateral cingulate and temporal lobes.Conclusions: There are alterations of brain volumetry and associated structural covariance within lobar regions in CSVD, which indicates the potential brain structural reorganization in CSVD. [ABSTRACT FROM AUTHOR]

The environmental pollution caused by waste plastics and their potential of resource recovery are receiving increasing attention. In this study, a molecular level kinetic model was established to simulate the polypropylene pyrolysis based on the SOL method, Poisson distribution model and genetic algorithm, which was simplified and effective without the introduction of extensive chemical databases and stiff differential equations. The automatic generation of complex reaction network was based on the representation of species and reactions at molecular level and the design of 14 reaction rules consistent with the mechanism. The model prediction achieved good agreement with experimental data affected by the primary and secondary reactions, verifying the generalizability of the models. The model prediction according to the kinetic parameters provided guidance for the pyrolysis experiments. In general, the molecular-level model behaves exquisite in the evaluation, validation, and prediction, and can gain an insight into the pyrolysis of polymers. • A molecular level kinetic model with automatic reaction network generation is established for polypropylene pyrolysis. • The automatic network generation is based on the Poisson distribution model, the SOL method and the design of reaction rules. • This model achieves excellent agreement with experimental data and can predict pyrolysis performance in more details. • The important role of temperature on the pyrolysis and the competition of two scissions are quantified by this model. [ABSTRACT FROM AUTHOR]

Aminopeptidase N (APN) is an important ectopeptidase involved in many physiological functions e.g. tumor angiogenesis, and the detection of APN activity thus facilitates the early diagnosis and elucidation of tumor development. Herein we propose a one-pot and one-step colorimetric sensing method for detecting APN activity based on a peptide functionalized gold nanoparticles/cucurbit[8]uril (pep-AuNPs/CB[8]) supramolecular structure. In principle, a peptide that comprises both the recognition sequence of APN and binding motif of CB[8] is first functionalized onto the surface of AuNPs. Because CB[8] can interact with two binding motifs simultaneously, the assembly of pep-AuNPs and CB[8] consequently take place, leading to the formation of pep-AuNPs/CB[8] supramolecular structure. However, in the presence of APN, the peptide will be hydrolyzed by APN, resulting in the breach of binding motifs of CB[8] as well as the prevention of the formation of pep-AuNPs/CB[8] supramolecular structure. In this way, the activity of APN can be determined through the absorbance changes based on the assembly/disassembly of AuNPs. Under optimized conditions, the detection of APN activity is achieved in a linear range from 5 μg/mL to 15 μg/mL with a detection limit of 0.42 μg/mL, which is also available directly in serum samples. Because of the simplicity and the cost-efficient materials, the method is competent for practical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • The I 2 nanotraps were used by introducing adjacent IBSs and LBSs on the skeleton. • The absorbent shows high I 2 uptake capacity (37 wt%) among all COF materials. • IBSs and LBSs synergistically promote iodine adsorption. Covalent organic frameworks have been recognized as promising porous materials for the radioactive iodine capture. However, most COFs often suffer from low adsorption capacity under practical conditions (typically ≥ 150 °C, ≤ 150 ppmv I 2) due to the lack of strong binding sites and low affinity toward iodine, which restricts their application in industrial relevant conditions. Here, we develop a strategy of constructing highly efficient I 2 nanotraps by manipulating two kinds of adsorption sites (ionic binding sites and Lewis binding sites) located at adjacent spatial positions, thereby realizing the synergistic binding toward I 2. The obtained I 2 nanotrap 4F-iCOF-TpBpy-I- delivers a remarkable I 2 uptake capacity of 37 wt% at 150 °C and 150 ppmv of I 2 , which illustrate a record-high value for all COFs reported so far. This work opens a new avenue for the rational design of COF materials toward highly efficient I 2 capture and related application. [ABSTRACT FROM AUTHOR]

α-MgAgSb is considered as a potential near-room-temperature thermoelectric material in virtue of its excellent electrical properties, ultralow lattice thermal conductivity and abundant constituent elements. However, it is hard to obtain high-quality phase pure α-MgAgSb due to its complex phase transition and high reactivity of element Mg, which cloaks material's intrinsic thermoelectric performance. Herein, through adopting a tantalum-sealing melting technique, we achieved highly-quality pure α-MgAgSb with large grain size and less oxygen content, as compared with our ball milled samples. The as-synthesized tantalum-sealing melted α-MgAgSb, without element doping or alloying, exhibited intrinsically low thermal conductivity, large weighted mobility, and high carrier concentration closes to the optimum range. Eventually, we attained a maximum thermoelectric figure of merit zT value of 1.3 at around 500 K in the tantalum-sealing melted α-MgAgSb. The average power factors and average zT values are also as high as 25 μW cm−1 K−2 and 1.1 respectively in the low-temperature range of (300 - 550) K, both of which rank as top values among the known materials. This study not only sheds new light on the understanding of intrinsic properties of α-MgAgSb but also demonstrates its great promise for harvesting low-grade waste heat. Record-high average power factor of 25 μW cm−1 K−2 and average zT of 1.1 were achieved in the melted α-MgAgSb sythesized by the tantalum-sealing melting technique. [Display omitted] [ABSTRACT FROM AUTHOR]

With the explosive economic development of China over the past few decades, air pollution has become a serious environmental problem and has attracted increasing global concern. Using satellite-based PM 2.5 data from 2000 to 2015, we found that the temporal-spatial variation of PM 2.5 in East China is characterized by high concentrations in the northern part and low concentrations in the southern part of East China, and by being seasonally high in autumn and winter but low in spring and summer. We also found that the regional average PM 2.5 concentration shows an approximative peak pattern over the last 16 years, with the highest, 60.13 μg m − 3 , and the lowest, 46.18 μg m − 3 , occurring in 2007 and 2000, respectively. Despite obviously diminishing heavy polluted regions with a PM 2.5 of > 80 μg m − 3 after 2011, those cells dominated by natural background have still not recovered back to the clean level of 2000. These characteristics are valuable information to analyze the relative contributions of anthropogenic emissions and atmospheric conditions to the temporal-spatial variation characteristics of PM 2.5 . [ABSTRACT FROM AUTHOR]

Abstract: The mixed-potential NOx sensor based on yttria-stabilized zirconia (YSZ) and oxide electrode is considered as a potential device used for the on-board diagnostics. Over the past decades, many researchers have paid their attentions on such YSZ based potentiometric NOx sensors and gotten a lot of achievement in developing new type electrode materials. Recently, in order to enhance the sensing performance of the mixed potential type NOx sensor, we have been focusing on modifying the triple-phase-boundary (TPB) by various techniques, including chemical corroding, the double-tape casting, the pore-forming and laser fabrication method. We also designed and prepared the microstructure of the oxide electrodes by controlling the sintering process for increasing the sensitivity of the NOx sensor. This paper reviews our works with regard to the above-mentioned two aspects. [Copyright &y& Elsevier]

Abstract: A series of mixed W/Cr oxides with different ratio of W and Cr (1:6, 1:2 and 3:2) have been prepared by using polymeric precursor method. By comparing their sensitivities to 20–300ppm NO2, it was found that the sensor using oxide with 3:2 W/Cr gave the largest response value. For 3:2 W/Cr oxide, the effect of the sintering temperature on the electrode microstructure was also investigated. As a result, the device sintered at 1000°C showed the best performance. The response value to 100ppm NO2 is 51.6mV, the response time is within 20s and the sensing device also shows an excellent selectivity against other coexisting gases. The characteristics of SEM and TEM revealed that the special microstructure of oxide electrode formed by sintering plays a significant role in better sensing performance. [Copyright &y& Elsevier]

Abstract: A series of tungstate MWO4 (M=Co, Zn and Ni) has been prepared by the polymeric precursor method. Meanwhile, yttria stabilized-zirconia (YSZ) based sensors using these oxides as sensing electrodes were investigated, and among the oxides tested, CoWO4 was found to be the most suitable for the sensing electrode (SE) of the ammonia sensor. The sensor attached with CoWO4 shows the fast response and recovery characteristics (not more than 5s respectively) and large sensitivity (−51mV/decade) at elevated temperature. The electric potential difference (∆V) of the sensor varies almost linearly with the NH3 concentrations in the examined range of 50–1000ppm. The SEM observation reveals that the special microstructure of CoWO4-SE, bulky rod-like crystals coated by tiny particles, plays a significant role in sensing performance. [Copyright &y& Elsevier]

Titanium oxide films were deposited on low temperature isotropic pyrolytic carbon (LTI-carbon) by ion beam enhanced deposition, and its mechanical properties such as ultramicrohardness, adhesion strength and fatigue property were studied. The microhardness of titanium oxide films prepared at different experimental conditions is maintained between 900 and 1000 kg/mm2, when measured by UMHT-3 ultramicrohardness tester installed in the scan electronic microscope. The adhesion strength measurement results show that the adhesion strength of titanium oxide films on LTI-carbon substrate is approximately 0.314–0.47 GPa. The deposition of Ti interlayer is beneficial to improve the adhesion strength of the film. Subsequently, the film with the highest adhesion strength was coated on mechanical heart valves, and the fatigue and wear resistance of the film was investigated in a simulated heart-valve-working environment. After 675 500 times of opening-and-closing cycles, a circular abrasion trail appeared, whereas titanium oxide was still present in this area. No peel of the film was observed. When the cycles increased to 1 617 000 times, a small part of the film located at the inboard boundary of the wear trail peeled off, however, Ti still could be detected in the wear trail region. [Copyright &y& Elsevier]

Soil moisture (SM) is a fundamental environmental variable for characterizing climate, land surface and atmosphere. In recent years, several SM products have been developed based on remote sensing (RS), land surface model (LSM) or land data assimilation system (LDAS). However, little knowledge is available in understanding spatial patterns of the uncertainty of different SM products and potential regional drivers over the Qinghai-Tibet Plateau (QTP), a complex environment for accurate SM estimation. This paper investigates the sensitivity of the SM uncertainties based on the three-cornered hat (TCH) method and a generalized additive model (GAM) in terms of underlying surface characteristics (sand fraction, soil organic matter, vegetation, land surface temperature, and topography) and near-ground meteorology (precipitation and air temperature) in the third pole environment over the 2015–2018 period. Eleven SM products are involved in this work, including Soil Moisture Active Passive (SMAP), Soil Moisture Ocean Salinity INRA-CESBIO (SMOS-IC), Japan Aerospace Exploration Agency (JAXA), Land Surface Parameter Model (LPRM), Climate Change Initiative - Active/Combined (CCI_A/CCI_C), Global Land Data Assimilation System (GLDAS), European Centre for Medium-Range Weather Forecasts Interim reanalysis (ERA-Interim), Global Land Evaporation Amsterdam Model product a/b (GLEAM_a/GLEAM_b), and Random Forest Soil Moisture (RFSM). Results show that most of the SM products perform well across QTP, while SMOS-IC is strongly affected by radio-frequency interference in this region, JAXA has a relatively higher noise level over QTP, and LPRM has larger relative uncertainties (RUs) in the southeast of QTP. Nonlinear regression analysis demonstrates that variations of RUs in SMOS-IC and JAXA are driven by topography, while LPRM's are mainly controlled by vegetation. In addition, two groups of opposite (positive/negative) effects from topography and vegetation, topography and precipitation, and precipitation and land surface temperature affect the spatial variations of RUs in CCI_A, RFSM, and ERA-Interim, respectively. Meanwhile, more complex relationships are found between multiple surface factors and RUs of different products. In general, the underlying surface factors explain on average 39.41% and 28.34% of the variations in RS and LSM/LDAS SM RUs, respectively. Comparatively, the near-ground meteorology factors have a slightly larger effect on LSM/LDAS products than that on RS products. • Three-cornered hat (TCH) method is used to estimate the uncertainties in multisource soil moisture products over the Qinghai-Tibet Plateau. • Field measurements from three in-situ networks are adopted to evaluate the estimated TCH results. • A two-stage data detection method is utilized to quantify the spatial variations in SM uncertainties. [ABSTRACT FROM AUTHOR]

• Few studies have analyzed the utilization of millet straw as raw materials in the preparation of superabsorbent resin. • The product had excellent water absorbency and slow-release property. • The product prepared by millet straw not only reduces production cost, but also promote plant growth. • Application of the fertilizer could achieve the goal of straw return to soil. To enhance utilization of waste straw and improve fertilizer efficiency, a novel semi-interpenetrating polymer network fertilizer (MSP-g-AA/PVA-APP) synthesized from straw cellulose and linear polymer was prepared by solution polymerization. The ammonium polyphosphate (APP) was introduced to supply nitrogen and phosphorus nutrients. The prepared materials were characterized with scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffractometry (XRD) and thermogravimetric analysis (TGA). The water absorbency and slow-release behavior of MSP-g-AA/PVA-APP were also studied. The results indicated that MSP-g-AA/PVA-APP exhibited excellent water absorbency of 681.3 g/g in distilled water and enhanced the water retention capacity of soil. The cumulative N and P release rates of MSP-g-AA/PVA-APP were 55.1 % and 47.3 % after 30 days in soil, respectively. The effect of MSP-g-AA/PVA-APP on growth of wheat was studied, and the results show that the application products could facilitate the growth of wheat. It could be concluded that the product with water retention and slow-release property, being low costs and friendly to environment, had great potential for application in agricultural. [ABSTRACT FROM AUTHOR]

• The droplet formation in electric periodic dripping regime was visualized. • The oscillation of electrified meniscus was visualized and identified. • The characteristic frequency deceases with an increase in applied potential. • The amplitude increases as electric number increasing. The dynamics of droplets and oscillation of electrified meniscus at low flow rates in an external electric field were investigated. An electric field is created by nozzle-plated electrode. The evolution of droplet formation is recorded by a high-speed digital camera. Meanwhile, the time evolution of meniscus is also focused. The critical sizes of the droplet and liquid thread were used to characterize the dynamics of droplet formation and oscillation of the meniscus. The results showed that a droplet gradually originates from a hemispherical meniscus and changes from spherical to pear-shaped. A liquid thread connects the meniscus and primary droplet, and pinches off as time advances. The droplets diameter decreases as electric potential increasing and is dependent of capillary diameter, while usually independent of flow rates. The droplet limiting length decreases, while the liquid thread diameter increases as electric Bond number increasing. The period of detachment decreases with an increase in electric potential and strongly depends on flow rate. The meniscus usually oscillates when the primary droplet detaches. The oscillation frequency increases as electric field strength increasing and is substantially affected by flow rate. An approximate equation to predict the oscillation frequency was presented, where the electric potential was taken into account. The variation of the oscillation frequency is qualitatively good agreement with experimental work. The amplitude of oscillation (or displacement) is significantly affected by electric field and increases as electric Bond number increasing. [ABSTRACT FROM AUTHOR]

• A new operational model with ant-miner algorithm was proposed to predict the risk of forest fires in cloud-rich areas. • The performance of proposed model was compared with that of the national risk prediction model of China. • The proposed model was compared to other risk prediction models with two classical machine learning algorithms. • The ant-miner algorithm-based model was more effective and reliable. Annually, millions of hectares of forest lands around the world are destroyed by fires. To minimize the fire-caused losses, more studies on the risk prediction of forest fires need to be carried out. For predicting the risk of forest fires in cloud-rich areas (e.g., the southwest of China), the synergetic use of operational forecasting systems and remote sensing-based models is expected to have a consistent performance. Therefore, we proposed in this study a new model based on ant-miner algorithm which has a good capability of solving multivariable and non-linear problems in the synergetic modeling of multi-source data. Based on historical fire data during 2000–2018 in Chongqing city, its performance was tested, and then was compared with that of other three models (i.e., meteorological data-, Artificial Neural Network-, and Support Vector Machine-based models). Results showed that, without interference from human factors, the risk predictions of proposed model were more objective. And, its mined-rules were easier to understand and also portable across multiple GIS platforms. Moreover, the proposed model has a better performance at predicting risk levels (i.e., overall accuracy was 79.02% and Kappa coefficient was 0.678) and the spatial distribution of its predictions were more detailed. This research indicated that the ant-miner algorithm-based model was more effective and reliable, and it could be used for constructing the operational system of risk predictions for forest fires in cloud-rich areas. [ABSTRACT FROM AUTHOR]

As a primary air pollutant, fine particulate matter (PM 2.5) is increasingly attracting attention. Crowdsourcing observations based methods are thought to be the best solutions for identifying the spatio-temporal distribution of PM 2.5 in intra-urban areas. However, inconsistent timing in the collection of crowdsourced data has typically been ignored in previous studies. To address this issue, a temporally calibrated method (TCM) was introduced in this study. By interpolating TCM-estimated observations using the inverse distance weighted (IDW) method, variations of PM 2.5 concentrations across the urban areas of Changsha City were captured. The results demonstrate that TCM can efficiently resolve the inconsistent timing defects of raw crowdsourcing observations (R 2 was 0.73 and the RMSE was 7.65 μg/m3). Furthermore, PM 2.5 distributions developed using TCM-based interpolations are of a finer spatial scale than those developed from raw observations at crowdsourcing locations. With a lack of funds to build sufficient stationary monitoring sites, developing crowdsourcing observation-based technology is the most promising solution for revealing intra-urban PM 2.5 variations at a higher spatio-temporal- resolution. Image 1 • A temporal calibration method was introduced for crowdsourcing air quality data. • TCM can eliminate time inconsistence of original crowdsourcing based PM 2.5 concentrations. • Intra-urban variations of PM 2.5 concentrations were revealed by densely observation. • Crowdsourcing observation is effective for fine scale air quality mapping in urban area. [ABSTRACT FROM AUTHOR]

A novel electrochemical biosensing method that can take into account both immunoassay and enzyme activity analysis was reported in this work for determination of the enzymatically active human apurinic/apyrimidinic endonuclease 1 (APE1). The basic principle is to design and construct a DNA catalytic hairpin assembly (CHA) triggered by APE1 catalysis in enzyme activity analysis, and the assembled DNAs are labeled with electrochemically active CdS and PbS quantum dots to output electrochemical signals. In this system, the signal generation needs to satisfy both the conditions of immunological recognition and enzymatic catalysis, providing a basis for accurate analysis of active APE1. Results show that this method can reflect the regulation of the enzyme activity and can also distinguish APE1 from its isozymes with the same enzyme activity. The concept and successful implementation of this integrated system will contribute to the research and application of APE1 in biomedicine, and provide a reference for the accurate analysis of other enzymes. Image 1 • A novel electrochemical biosensing system is developed for the detection of APE1. • The strategy skillfully integrates immunoassay with enzyme activity analysis through an elaborate design. • The detection limit of APE1 biosensor is as low as 0.00518 U/mL. • The strategy can monitor the regulation of the enzyme activity by an inhibitor and discrimination of APE1 from its isozyme. [ABSTRACT FROM AUTHOR]